Before reducing the radical, what number is under the square root symbol? A.81 B.144 C.50 D.63

D. 63

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to Right  

Equality Properties

Multiplication Property of Equality Division Property of Equality Addition Property of Equality Subtraction Property of Equality

Algebra I

Terms/Coefficients

Trigonometry

[Right Triangles Only] Pythagorean Theorem: a² + b² = c²

a is a leg b is another leg c is the hypotenuse

Step-by-step explanation:

Step 1: Identify Variables

Leg a = 9

Leg b = b

Leg c = 12

Step 2: Solve for b

Substitute in variables [Pythagorean Theorem]:                                          9² + b² = 12²[Subtraction Property of Equality] Isolate b term:                                        b² = 12² - 9²Evaluate exponents:                                                                                       b² = 144 - 81Subtract:                                                                                                          b² = 63[Equality Property] Square root both sides:                                                  b = √63